The present invention relates to the field of routing in hybrid telecommunications networks also known as wireless mesh networks (WMN).
Such networks enable ad hoc mobile telecommunications networks to interface with an infrastructure network via access points (or gateways), where an ad hoc network is one in which mobile units called “nodes” are free to move around and to communicate wirelessly with another.
Hybrid networks serve, in particular, to solve the known scaling and performance problems of ad hoc mobile networks. Moreover, the infrastructure network integrated with the ad hoc network considerably strengthens control and security.
The nodes in a hybrid network covered by the same access point form an ad hoc network. When two ad hoc networks overlap, even partially, they form a larger ad hoc network.
In a hybrid network, a message sent by a source node to a destination node can be routed end-to-end within the ad hoc network or via the access points.
The invention is more particularly directed to searching for the best route for routing a message between a source node and a destination node in a hybrid network.
Considerable research has been done on the problem of determining a routing protocol that is effective in a hybrid network.
Existing solutions at present can be classified in two categories.
In solutions in the first category, each node of the network uses its own topology search algorithms and maintains its knowledge of the topology itself. These solutions are not modular and consume computation power in each of the nodes, which can be a problem when the nodes have limited energy resources. Moreover, the total traffic generated by all the nodes for the purposes of such control can become very high if the number of nodes increases.
In the second category of solutions, each node of the network periodically informs the access point about the states of the relevant links, the access point using this information to maintain knowledge of the entire topology of the network. Continuous updating of the entire topology of the network by the access point requires a very large quantity of control traffic dedicated exclusively to this purpose. Now, it is legitimate to consider that at any given time not all nodes are active, i.e. likely to communicate with another node or with an access point. Such solutions therefore generate unnecessarily control packets that are highly redundant.